Carburetor



March 15 w35 A, E, WEAVER CARBURETOR Filed Sept. 3. 1921 HIIIIIIYII 3mm/Hoz HV1/@aver sufro Y i Patented Mar. 15, 1927.

ALBERT E. WEAVER, F INDIANAPOLTS,

TNDIANA, .AYSSIGNOR, BY MESNE ASSIGN- MENTS, TO IRA T. SWARTZ, TRUSTEE, OF INDIANAPOLIS, INDIANA.

Application filed September 3, 1921.

This invention relates to automatic eX- pansible venturi of that class adapted to be used in connection with carburetors, or the like, for controlling the admission of air into or through parts of the carburetor. The

prime feature of the invention is the provision of a plurality of overlapping tongues or fins which will readily expand or contract due to vacuum created by the engine to which the carburetor is attached.

A further feature of the invention is in so constructing the venturi that it may be of one solid or continuous piece, the tongues or fins being integral with the body portion of the venturi.

A further feature of the invention is in so arranging the tins that when in collapsed position they will practically close communication through the air intake of the carburetor.

Other objects and advantages will be hereinafter more fully set forth and pointed out in the accompanying specication.

In the accompanying drawings,

Figure 1 is a vertical central sectional view through a carburetor showing the improved venturi applied to use therein,

Figure 2 is a sectional view as seen on line 2 2 Figure 1, and

Figure 3 is an enlarged section of the venturi and parts to which it is attached showing the venturi in expanded or open position.

Referring to the drawings, 1 indicates the bowl portion of a carburetor, which may be of any preferred construction, in which is formed an air inlet passage 2, the dome 3 of the carburetor being connected with the bowl 1 by means of a tube 4, the lower end of said tube communicating with the air inlet passage 2.

Extending upwardly through the bowl 1 is a nozzle 5 through which the liquid fuel is conveyed into the tube 4, the upper end of the nozzle 5 being surrounded by a tubular sleeve 6, said sleeve beingl employed primarily for controlling the air when the engine is idling or running at low speed, the lower portion of the sleeve 6 having ports 7 for the admission of air which passes between that portion of the nozzle within the sleeve and the wall of the sleeve.

It is customary to mount a venturi within the tube 4 for properly mixing the air pass- Serial No. 498,337.

ing through the inlet 2 with the fuel entering the tube 4, but in the ordinary form of venturi it requiresone or more valves for co-operation therewith. In the present invention the venturi 8 is so constructed that it not only controls the passage of the. air` into the tube 4, but serves as a valvefor closing communication between the passage 2 and tube 4, and to this end the venturi 8 is composed of a band-like body 9 which ts the interior of the tube 4, and on the upper edge of said body are formed a series of tongues or fins 10, the lower ends of which are integral with the body 9. The fins 10 are directed inwardly at their free ends so that the venturi is substantially cone-shaped, one 'edge of each 'fin overlapping the adjacent edges of the next succeeding fin, so that when the fins expand or contract they will properly nest with each other, and when fully closed will practically cut ofi' the flow ofair from the passage 2 into the tube 4. With this construction the volume of air admitted to the tube 4 will be properly controlled, depending entirely upon the speed of the engine as to the volume of air admitted, as when the speed of the engine increases the vacuum in the dome portion of the carburetor will be increased, consequently acting to expand or spread the fins 10, and increase the diameter of the opening between the free ends of the fins and the tubular sleeve 6, while a limited amount of air will pass between the overlapping edges of the fins. Likewise. as the speed of the engine decreases the fins 10 will gradually contact or nest, one upon the other, and gradually decrease the diameter of the opening between the free endsl of the iins and the tijibular sleeve, thereby cutting oft' the supply o air.

This form of venturi is entirely automatic, as the operation thereof is controlled entirely by the speed of the engine, or rather the vacuum created by the engine in the dome portion of the carburetor.

This device can be very cheaply manufactured and materially reduces the cost of production of the parts of the carburetor owing to the fact that certain elements of the carburetor may be eliminated, and when once applied to use is practically indestruc tible, and when once installed will be positive in its operation.

Having thus fully described my said invention, what I claim as new and desire to secure by Letters Patent, is:

l. ln a carburetor, a bowl, an angular air inlet concentric at its upper end with said bowl, tubular fuel spraying means located centrally of said inlet at its upper end, a dome having a rim matching that ol the bowl and having a transverse apertured web, a tube leading from the air inlet to 'the aperture in the web and an automatically expansible venturi carried by the tube normally in close engagement with the spraying means, substantially as set forth.

2. In a carburetor, a sprayingvnozzle, a tube surrounding said nozzle in spaced relation thereto and having an air inlet passage through the tube into the passage around the nozzle, a second tube surrounding said first-mentioned tube for supplying air around and into said iii-st mentioned tube for commingling with the Yfuel to be supplied by the carburetor, a collapsible venturi carried by said second tube and collapsible i toward the first tube for cutting off the supply of air between the first and second tubes and eXpansible to permit air to flow through its end about said tirst tube but preventing the flow of air between said iirst and second tubes except through the end of said venturi, substantially as set forth.

8. A carburetor comprising a bowl having an integrallyv formed air inlet passage, a dome on the bowl, a sleeve connecting said bowl and dome and forming a continuation of said air inlet passage, a tube fixed in said air inlet passage and having a fuel passage leading` from the bowl to the sleeve said tube being provided with air inlet passages intermediate its ends, a nozzle within the tube terminating below the upper end thereof, a needle valve adjustably secured in the bottom of the bowl for varying the flow through the nozzle, and an automatic expansible venturi secured to said sleeve at the upper end oi' the air inlet passage said venturi comprising lins arranged so that their free ends normally rest against the tube adjacent its upper endv and which may be expanded by the suction of the engine, substantially as set forth.

ln witness whereof, I have hereunto set my hand at Indianapolis, Indiana, this 25th day of August, A. D. nineteen hundred and twenty-one.

ALBERT E. WEAVER. 

